fossil

Fossiliferous limestone, likely coral limestone

Bioclastic calcite (CaCO₃), commonly derived from fossil coral or shell material

AI-generated identification · may be incorrect

Soft to moderately hard (Mohs 3); pale gray-white, dull to faintly sugary luster, porous texture, and irregular rounded cavities resembling coral or dissolved shell structures. Calcite-rich material effervesces readily with dilute hydrochloric acid or vinegar, though vinegar is weaker.

Identified August 21, 2026More fossil →

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At a glance

Common name: Fossiliferous limestone, likely coral limestone
Scientific name: Bioclastic calcite (CaCO₃), commonly derived from fossil coral or shell material
Category: fossil
Identified: August 21, 2026
Method: Standard

AI Estimated Value

About $5–$25 for a common hand specimen; $30–$100+ if the coral or fossil structure is unusually clear, attractive, or locality-documented.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms from accumulated marine skeletal debris, reef frameworks, or carbonate mud later cemented and lithified into limestone; age may range from Paleozoic to Cenozoic depending on locality. The cavities can result from original fossil pores or later dissolution.

Uses & applications

Used as decorative stone, educational specimens, aggregate, cement and lime feedstock; attractive pieces may be collected or displayed, but it is generally not suitable for jewelry.

Geological facts

The visible holes may represent corallites, shell voids, or weathered vugs rather than volcanic vesicles. A white powder or scratch under a steel knife supports calcite-rich limestone identification.

Field identification & locations

Common in former shallow tropical seas and limestone regions worldwide, including Florida, the Caribbean, Mediterranean, and many coastal sedimentary basins. Confirm with acid fizz, low hardness, and fossil-like patterning; exact fossil identification requires a closer view.